Solve the quadratic equation x2−3(x+3)=0; Give your answer correct to two significant figures.
x2−3(x+3)=0⇒x2−3x−9=0
Here, a=1, b=−3, c=−9
So, x=−b±√b2−4ac2a=3±√(−3)2−4×1×(−9)2×1=3±√452=3±6.7082⇒x=4.85 or x=−1.85
Solve the following equation and give your answer correct to 3 significant figures:
5x2−3x−4=0